externals: Update fmt subtree to 4.10

Merge commit '097203968f' into HEAD

externals/fmt/doc/api.rst

@@ -84,6 +84,36 @@ Note in the example above the ``format_arg`` function ignores the contents of
 ``format_arg`` in :file:`fmt/time.h` for an advanced example of how to use
 the ``format_str`` argument to customize the formatted output.
 
+This technique can also be used for formatting class hierarchies::
+
+  namespace local {
+  struct Parent {
+    Parent(int p) : p(p) {}
+    virtual void write(fmt::Writer &w) const {
+      w.write("Parent : p={}", p);
+    }
+    int p;
+  };
+
+  struct Child : Parent {
+    Child(int c, int p) : Parent(p), c(c) {}
+    virtual void write(fmt::Writer &w) const {
+      w.write("Child c={} : ", c);
+      Parent::write(w);
+    }
+    int c;
+  };
+
+  void format_arg(fmt::BasicFormatter<char> &f,
+                  const char *&format_str, const Parent &p) {
+    p.write(f.writer());
+  }
+  }
+  Local::Child c(1,2);
+  Local::Parent &p = c;
+  fmt::print("via ref to base: {}\n", p);
+  fmt::print("direct to child: {}\n", c);
+
 This section shows how to define a custom format function for a user-defined
 type. The next section describes how to get ``fmt`` to use a conventional stream
 output ``operator<<`` when one is defined for a user-defined type.
@@ -232,6 +262,8 @@ Utilities
 
 .. doxygenfunction:: fmt::to_string(const T&)
 
+.. doxygenfunction:: fmt::to_wstring(const T&)
+
 .. doxygenclass:: fmt::BasicStringRef
    :members:
 

externals/fmt/doc/build.py

@@ -6,6 +6,8 @@ import errno, os, shutil, sys, tempfile
 from subprocess import check_call, check_output, CalledProcessError, Popen, PIPE
 from distutils.version import LooseVersion
 
+versions = ['1.0.0', '1.1.0', '2.0.0', '3.0.2', '4.0.0', '4.1.0']
+
 def pip_install(package, commit=None, **kwargs):
   "Install package using pip."
   min_version = kwargs.get('min_version')
@@ -93,11 +95,11 @@ def build_docs(version='dev', **kwargs):
   if p.returncode != 0:
     raise CalledProcessError(p.returncode, cmd)
   html_dir = os.path.join(work_dir, 'html')
-  versions = ['3.0.0', '2.0.0', '1.1.0']
+  main_versions = reversed(versions[-3:])
   check_call(['sphinx-build',
               '-Dbreathe_projects.format=' + os.path.abspath(doxyxml_dir),
               '-Dversion=' + version, '-Drelease=' + version,
-              '-Aversion=' + version, '-Aversions=' + ','.join(versions),
+              '-Aversion=' + version, '-Aversions=' + ','.join(main_versions),
               '-b', 'html', doc_dir, html_dir])
   try:
     check_call(['lessc', '--clean-css',

externals/fmt/doc/index.rst

@@ -143,6 +143,12 @@ its numeric value being written to the stream (i.e. 1070 instead of letter 'ю'
 which is represented by ``L'\x42e'`` if we use Unicode) which is rarely what is
 needed.
 
+Note that fmt does not use the value of the ``errno`` global to communicate
+errors to the user, but it may call system functions which set ``errno``. Since
+fmt does not attempt to preserve the value of ``errno``, users should not make
+any assumptions about it and always set it to ``0`` before making any system
+calls that convey error information via ``errno``.
+
 .. _portability:
 
 Portability

externals/fmt/doc/syntax.rst

@@ -335,6 +335,16 @@ Aligning the text and specifying a width::
    format("{:*^30}", "centered");  // use '*' as a fill char
    // Result: "***********centered***********"
 
+Dynamic width::
+
+   format("{:<{}}", "left aligned", 30);
+   // Result: "left aligned                  "
+
+Dynamic precision::
+
+   format("{:.{}f}", 3.14, 1);
+   // Result: "3.1"
+
 Replacing ``%+f``, ``%-f``, and ``% f`` and specifying a sign::
 
    format("{:+f}; {:+f}", 3.14, -3.14);  // show it always
@@ -350,7 +360,7 @@ Replacing ``%x`` and ``%o`` and converting the value to different bases::
    // Result: "int: 42;  hex: 2a;  oct: 52; bin: 101010"
    // with 0x or 0 or 0b as prefix:
    format("int: {0:d};  hex: {0:#x};  oct: {0:#o};  bin: {0:#b}", 42);
-   // Result: "int: 42;  hex: 0x2a;  oct: 052;  bin: 0b101010"
+   // Result: "int: 42;  hex: 0x2a;  oct: 052;  bin: 0b101010"   
 
 .. ifconfig:: False
 
@@ -359,13 +369,6 @@ Replacing ``%x`` and ``%o`` and converting the value to different bases::
       format("{:,}", 1234567890);
       '1,234,567,890'
 
-   Expressing a percentage::
-
-      >>> points = 19
-      >>> total = 22
-      Format("Correct answers: {:.2%}") << points/total)
-      'Correct answers: 86.36%'
-
    Using type-specific formatting::
 
       >>> import datetime

externals/fmt/doc/usage.rst

@@ -41,6 +41,10 @@ current directory. Now you can build the library by running :command:`make`.
 Once the library has been built you can invoke :command:`make test` to run
 the tests.
 
+You can control generation of the make ``test`` target with the ``FMT_TEST``
+CMake option. This can be useful if you include fmt as a subdirectory in
+your project but don't want to add fmt's tests to your ``test`` target.
+
 If you use Windows and have Visual Studio installed, a :file:`FORMAT.sln`
 file and several :file:`.vcproj` files will be created. You can then build them
 using Visual Studio or msbuild.